Patent GB-570178-A (GB)
Title: Improvements in and relating to recocking devices for automatic guns
IPC: F41A7/04
Filed: 1943-05-21
Abstract: 570,178. Automatic guns. SPECIAL TIES DEVELOPMENT CORPORATION. May 21, 1943, No. 8138. Convention date, Aug. 14, 1942. [Class 92 (ii)] Relates to recocking mechanism for automatic guns, of the kind in which the mechanism is controlled by means, such as a valve 31, Fig. 2, which is itself controlled by an electrically-operated device in turn controlled by means controlled by a member movable with the breech mechanism, the arrangement being such that the recocking device is brought into operation if the breech mechanism slows down or stops. According to the invention, the means controlled by the movable member comprises current generating means operated by the movable member. As shown diagrammatically in Fig. 2, the breech casing of a gun has a slot 15 through which projects a stud 14 connected to and oscillating with 'the breech mechanism. In front of the forward position of the stud is a cylinder 21 containing a spring- controlled plunger 22, the rod 23 of which has a head 24 which, when the cylinder is supplied with compressed air, carbon dioxide or other gas, strikes a rider assembly 25 secured to the stud 14. Gas enters the cylinder through a tube 29 and valve inlet 30, the latter normally being held closed by a member 37 under the influence of a spring-controlled bell-crank lever 42. A solenoid 50 is adapted when energized to rotate the lever against the action of its spring 47. Gas then enters the cylinder and ram 24 contacts assembly 25 to drive the breech mechanism. A lever 51 may be arranged as shown to be struck by a projection 54 on assembly 25 and thus to actuate a rod 55 to cause member 37 to return to the valveclosing position. In this position of the member 37, the cylinder 21 is connected to the atmosphere by way of port 35, and thus the plunger 22 can return under the action of its spring. The rider assembly 25 is connected by a bracket 62 carrying a permanent magnet 61 which, under normal firing conditions, oscillates within a coil 60. As shown in Fig. 3, the alternating current thus produced is rectified to supply current to a relay 71. Current is also supplied to the relay by a battery 70, and resistances 74, 75 and 76 are arranged as shown in the circuit in such manner that the voltage e across resistance 76 substantially equals the voltage E across resistance 75 under normal firing conditions. Little or no current therefore flows through the relay 71 when a switch 77 connected to the trigger mechanism is closed, arid a switch 72 associated with the relay therefore remains in the open position shown. When jamming or slowing down of the breech mechanism occurs, the potential across resistance 76 drops and a current flows through the relay to close switch 72. By the closing of the switch current from the battery flows through wires 97, 99 to the solenoid 50, thus moving lever 42 to open the valve for the gas leading to the cylinder 21 of the recocking device. In a modification, Fig. 4, the rectified current from the coil 60 energizes a solenoid 115 which maintains a switch 111 in circuit with solenoid 50 in an open position. When the trigger is pulled, a switch 77<1> connected to a battery 70<1> is closed and energizes a solenoid 104 to close a switch 101. When the breech mechanism slows down or jams, the current to solenoid 115 decreases or ceases and switch 111 is pulled by a spring 114 to a position in which it closes the circuit containing the switches 77<1> 101 and solenoid 50. The solenoid is thus energized to actuate the recocking mechanism.